The point is you haven't solved the problem. You've just moved it to a different place. Urban sprawl is pretty well acknowledged to be a bad thing (TM) - it increases pollution, is bad for people's health, bad for the social fabric, etc etc.

Saying "it's crowded here, let's go move somewhere else and make that crowded" is not just kicking the can, it's making the problem worse because often those areas have even less mass transit.